Apparatus for vaporizing and igniting cold liquid fuel



FUEL

July 5, 1955 P. A. MANOR ETAL APPARATUS FOR VAPORIZING AND IGNITING COLD LIQUID Filed NOV. 28, 1950 2,712,352 Patented July 5, 1955 APPARATUS FOR VAPGRIZING AND IGNITING COLD LIQUID FUEL Paul A. Manor and John K. Siddle, signors to Surface Combustion Ohio, a corporation of Ohio Application November 28, 1950, Serial No. 197,976 6 Claims. (Cl. 158-28) Columbus, Ohio, as- Corporation, Toledo,

tory to starting the engine. vaporized and ignited is the same as is used by the engine which is to be started and its characteristics are best illustrated by the statement that an open can of this fuel at minus 65 F. starts to burn very slowly where the flame of a blow torch is applied to the surface of the fuel. Moreover where an electric storage battery has been eX- posed for hours to a low temperature it is likely to be subnormal in voltage which further complicates the problem where electric current from the battery must be utilized to operate the vaporizing and igniting means for said The primary object of the present invention is to provide a vaporizing and igniting system for cold liquid fuel which shall be dependable in operation at low Arctic temperatures with electric current from a storage battery whose voltage may be as low as eight volts. Other related objects will more fully appear hereinafter.

For a consideration of what we believe to be novel and our invention attention is directed to the following portion of the specification and the drawings and concluding claims thereof.

In the drawings:

Fig. 1 shows the improved heater in axial section with a portion in elevation and with a portion intermediate the ends of the heater omitted.

Fig. 2 is a fragmentary end elevation and section on line 2-2 of Fig. 1.

Fig. 3 is a fragmentary sectional view on line 33 of Fig. 1.

Fig. 4 is diagrammatic view of the electrical system for operating the heater.

Fig. 5 is a miniature view of a truck to illustrate the type of motor vehicle wherein the heater of the present invention will normally be embodied as part of the engine starting equipment.

The heater will ordinarily be of the type comprising an annular heating space 8 between outer and inner cylindrical shells 9 of bell-type shape secured together by an annular connecting plate 11. The will ordinarily be the coolant for an Pipe 13 conducts said coolant to said heating space and pipe 14 conducts it therefrom.

the present invention, the burner comprising a cylindrical wall 16 and an end wall 21, the cylindrical wall having a tangential inlet 17 for air under pressure conducted to said inlet by a supply pipe 18 leading from a blower 20 (see Fig. 4). The end wall 21 issecured gas tight'to a rim flange on the adjacent end of the cylindrical wall 16 as by bolts 22. At its inner end the cylindrical wall 16 has a rim flange 23 through which bolts 29 may be passed for detachably securing said wall 16 to a rim flange 24 extending from the annular plate 11. Clamped between the two flanges 23 and 24 there is a rim flange 25 of a fire tube 26 which provides a fire chamber for the fuel issuing from the burner 15 and which terminates short of the end wall 27 of the inner heater shell 10 and which tube is radially spaced from the cylindrical wall of the extends radially through the cylindrical walls of the heater shells 9 and 10 near the annular connecting plate 11 for the latter. To the exterior surface of said fire tube 26 there will ordinarily be secured in longitudinally staggered relation a multiple series of tab-like baffle elements 32 to produce in the stream shell 10 of the heater.

The means for vaporizing and igniting the cold liquid fuel comprises wick means generally indicated numeral 33, an electrical heating coil 46, and a spark electrode 47.

as eight volts; is reduced to a minimum.

The composite wick 33 is made of materials having diiferent properties. The metal wick 34 is relatively high- 6 and the metal wick 34 thereafter provides increased vaporizing capacity, as well as structural benefits, and acts as a ground for the spark ignition.

The main wick 34 is mounted on the end wall 21 of the burner to project a substantial distance into the space encompassed by the cylindrical wall 16, the end wall 21 having a central aperture through which said wick extends. The liquid fuel is fed to said wick by a supply pipe 36 having a shut-off valve 37 which will ordinarily be operated by a solenoid 38. The discharge end of said pipe 36 preferably terminates within the upper end of a relative narrow sealed container 40 into which a substantial portion of the wick 34 extends for receiving on its upper side the fuel from said pipe. The lower portion 41 of said container 40 serves as a reservoir for receiving any overflow of fuel from said wick. A drain trough 42 from said reservoir conducts the excess fuel to a point within the fire tube 26 so that it may eventually be burned therein. The wick 34 is held in fixed position as by providing on the outer end thereof a rim flange adapted to be clamped against the outer face of the outer wall 43 of said container 40 by a clamping plate 44 having a central hollow hub 45. A plug 48 screwed into said hub 45 supports the heating coil 46. The electrode 47 is conveniently supported by a rod 51 projecting from a plug 52 mounted on the cylindrical wall 16. The source of electric current for operating the heating coil and spark electrode is a battery 49 carried by a vehicle 39 as part of its electrical system.

The electric control system for the heater may comprise a normally closed thermostatic switch 53 positioned in the exhaust thimble 31 of the heater for shutting off current to the heating coil 46 when the temperature of said switch exceeds 100 F. and may also comprise a normally closed thermostatic switch 54 responsive to the temperature of the heat transfer medium being heated for shutting off the heater when the temperature of said medium reaches a predetermined degree. A starting switch in the battery circu't is indicated at 55. In normal operation, starting from cold, when the starter switch 55 is closed, current from the battery 49 flows to the heating coil 46 by way of the normally closed switches 54 and 53. Current also flows to the solenoid 38 by way of the switch 54 to open the fuel valve 37. Current also flows to an open core induction coil 56 which in turn energizes the spark electrode 47. Current also flows to the motor for the air blower 20.

It is found advantageous to provide within the fire tube 26 an annular baffle 57 co-axial with said tube to accelcrate combustion of the whirling mass of air and fuel by the resulting increase in turbulence in said mass on passing through the relatively restricted central aperture in said baffie. The heat radiated from said bafiie to the end wall 2.1 of the burner also helps to maintain said wall sufficiently warm to melt off the frost on the exterior surface of said wall. A second annular baffle 58 may also be mounted within said tubular number '26 down stream from the front baffle 57 to cause additional turbulence in the advancing products of combustion before they pass from said fire tube 26.

From the foregoing explanation it may now be seen that the present invention provides a vaporizing and igniting system for liquid fuel which is well adapted for the intended purpose.

What is claimed as new is:

1. Structure for a forced air liquid fuel burner which comprises a tubular mass of sintered and compacted metal granules forming a main wick, means for delivering fuel to the main wick, a relatively thin layer of asbestos fibres forming a pilot wick arranged within and in contact with the main wick to receive liquid fuel therefrom, an electric heating coil arranged within the space encompassed by said wick, and a spark electrode located adjacent the pilot wick for igniting vaporized fuel from the wick.

2. Structure according to claim 1 and comprising a metal 4 ring within said pilot wick for holding it in position in said main wick.

3. Structure according to claim 1 wherein said main wick constitutes a ground for said spark electrode.

4. In a heater for use in Arctic regions, in combination, means comprising an end wall forming a combustion chamber; an annular wick comprised of an inner portion of low fuel transmitting, poor heat conductive material and an outer portion of highly heat conductive, fuel transmitting material, said wick being adiacent the end wall and forming a fuel vaporizing chamber within the wick, one end of the chamber being in open communication with the combustion chamber; an electric heating coil disposed in the fuel vaporizing chamber in heat radiating relation to the inner walls of the wick; an electrode adapted to discharge a spark in igniting proximity to combustible mixtures formed in the fuel vaporizing chamber; fuel supply means for supplying fuel to the wick; means for supplying electrical energy to the heating coil to heat the coil; and means for supplying electrical energy to the electrode to produce a spark therefrom.

5. In a heater for use in Arctic regions, in combination, means comprising an end wall forming a combustion chamber; an annular wick comprised of an inner annular portion of an asbestos-type wick material and an outer annular portion of metallic wick material, said wick being adjacent the end wall and forming a fuel vaporizing chamber within the wick, one end of the chamber being in open communication with the combustion chamber; an electric heating coil disposed in the fuel vaporizing chamber in heat radiating relation to the inner walls of inner side surfaces of the recess between the Wick; an electrode adapted to discharge a spark in igniting proximity to combustible mixtures formed in the fuel vaporizing chamber; fuel supply means for supplying fuel to the wick; means for supplying electrical energy to the heating coil to heat the coil; and means for supplying electrical energy to the electrode to produce a spark therefrom.

6. in a heater for use in Arctic regions, in combination, means forming a combustion chamber, means for supplying fuel and air to the combustion chamber, and means for igniting the fuel comprising a recess that is closed at one end and has its other end opening into the combustion chamber, an asbestos-type wick material forming the the ends thereof, an electrical resistance heating element so arranged in the recess that such asbestos-type wick material surrounds and receives a substantial portion of the heat radiated from the heating element, the recess also having a substantial air space therein, means for supplying liquid fuel to the asbestostype wick material, whereby such fuel is vaporized at the surface of the wick material by reason of the relatively high temperature to which such surface is heated by the heating element because of the low heat conductivity of the wick material, and means forming a spark gap arranged to discharge a spark to ignite a cornbustible mixture of air with vapor that has been collected in the air space in the recess.

References Cited in the file of this patent UNITED STATES PATENTS 701,241 Young May 27, 1902 1,555,631 Brown Sept. 29, 1925 2,052,514 Kinsman Aug. 25, 1936 2,159,257 Danuser et al May 23, 1939 2,192,389 Trca Mar. 5, 1940 2,286,854 Holthouse June 16, 1942 2,431,456 Bock Nov. 25, 1947 2,445,341 Trimble et a1. July 20, 1948 2,447,373 Smoot Aug. 17, 1948 2,474,687 Parrish June 28, 1949 2,494,785 Tramontini et al. Jan. 17, 1950 2,520,159 Long Aug. 29, 1950 2,584,281 Morlock Feb. 5, 1952 

6. IN A HEATER FOR USE IN ARCTIC REGIONS, IN COMBUSTION, MEANS FORMING A COMBUSTION CHAMBER, MEANS FOR SUPPLYING FUEL AND AIR TO THE COMBUSTION CHAMBER, AND MEANS FOR IGNITING THE FUEL COMPRISING A RECESS THAT IS CLOSED AT ONE END AND HAS ITS OTHER END OPENING INTO THE COMBUSTION CHAMBER, AN ASBESTOS-TYPE WICK MATERIAL FORMING THE INNER SIDE SURFACES OF THE RECESS BETWEEN THE ENDS THEREOF, AN ELECTRICAL RESISTANCE HEATING ELEMENT SO ARRANGED IN THE RECESS THAT SUCH ASBESTOS-TYPE WICK MATERIAL SURROUNDS AND RECEIVING A SUBSTANTIAL PORTION OF THE HEAT RADIATED FROM THE HEATING ELEMENT, THE RECESS ALSO HAVING A SUBSTANTIAL AIR SPACE THEREIN, MEANS FOR SUPPLYING LIQUID 